color halftone
An effect that can be seen when printed media is scanned at very high resolution, causing solid colors to appear as dotted patterns.
For more information on how to remove screening from scans, see: yande.re [Danbooru forum #2007](https://danbooru.donmai.us/forum_posts/2007), yande.re [Danbooru forum #2290](https://danbooru.donmai.us/forum_posts/2290).